Needle for weaving machines of the continuous weft-feed type



R. DEWAS Aug. 11, 1964 NEEDLE FOR WEAVING MACHINES OF' THE CONTINUOUS WEFT-FEED TYPE Filed NOV. 26, 1962 ATTO rLN e 55 3,144,051 NEEDLE FOR WEVING MACHINES OF THE CONTINUOUS WEET-FEED TYPE Filed Nov. 26, 1962 R. DEWAS Aug. 11, 1964 2 Sheets-Sheet 2 INVENTOR: R.Dewc1.s

las mickfohf/VJ ATTO TAN E SS United States Patent 3,144,051 NEEDLE FOR WEAVIN G MACHINES OF THE CONTINUOUS WEFT-FEED TYPE Raymond Dewas, 120 Blvd. de St.-Quentiu, Amiens, France Filed Nov. 26, 1962, Ser. No. 240,072 Claims priority, application France Dec. 1, 1961 4 Claims. (Cl. 139-423) The present invention relates to weaving machines of the type in which the weft is continuously fed from large bobbins located outside the shed.

Certain classes of these machines are provided for the purpose of weft insertion, either with a single weft-inserter or needle, or two oppositely-directed weft-inserters or needles, one of which brings the weft to the middle of the shed where the other takes the weft and draws it across the remaining half of the shed.

The invention is concerned with the needles which are employed especially in looms of substantial width and which are usually composed of two elements, namely, a flexible band, and a rigid portion which in turn comprises a needle body and a head, the needle body being fixed on the front portion of the band, A driving wheel having teeth or projections meshes with perforations in the band and imparts a reciprocating motion to the needle.

Outside the shed, each edge of the band is engaged in rectilineal slideways having arcuate extensions which direct the band beneath the loom.

The top portions of the slideways clear the path of the needle body and guide only the marginal portions of the band.

At the end of its outward travel, the needle body is located above the driving wheel which is located between the rectilineal slideways.

Irrespective of the prole of the wheel teeth, the band is accordingly lifted in the meshing zone, and thus the band has a tendency to jam in the slideways; this results in accelerated wear of the band and even fractures in the perforation zone, which thus puts the band out of service. This tendency of the band to jam increases the fatigue of the wheel teeth and of the devices which actuate the wheel, all this results in an increase in the consumption of driving power.

In order to provide stability to the band, there can be placed either on one side or on both sides of the wheel and in the meshing zone, slideway guides or rollers which cover one edge or both edges of the band up to the immediate vicinity of the wheel. While the result thus achieved is a substantial increase in the useful life of the bands, the use of the above-mentioned means nevertheless makes it necessary to place the wheel beyond the farthest point reached by the rear end of the needle body, thereby increasing the length of the lay and therefore the overall size of the machine; this makes it necessary to set the wheel and its driving members in a position which is less favourable from all points of view.

An object of the present invention is to permit the use of said means while at the same time overcoming the disadvantages mentioned above.

To this end, the invention has for one of its objects the provision of a weft inserting needle having a body with a flat base applied against one face of the band and having a front portion and a rear portion. The front portion has the maximum width which is compatible with the band guiding slideways in order that the needle body may be perfectly Seated with a view to providing the head of the needle with the requisite stability and also with a view to ensuring that the corresponding portion of the band is perfectly straight and, therefore, correctly engaged inside the guides which are set at intervals along the path of the travel of the band through the shed. The rear portion of the needle is so shaped that the top face of the band is left free, at least on one side of the driving wheel, thereby making it possible to provide members which limit the lifting movement of the band in the meshing zone, and also to set the Wheel in a favourable position on the lay.

In accordance with one embodiment, the rear portion of the base of the needle body is provided only on one side of the driving wheel and is fixed on the corresponding edge of the band.

In accordance with another embodiment, the rear por-V tion of the base of the needle body is provided only in the zone of perforations of the band and is ixed at intervals in the spaces between the said perfora'tions.

The above-mentioned characteristic features and advantages will be clearly understood from the following description of said embodiments which are given solely by way of example without any limitation being implied, and which are diagrammatically illustrated .in the accompanying drawings, in which:

FIG. l is a longitudinal vertical section taken along the line I-I--I-II"I of FIG. 2 and shows one embodiment of the needle body and flexible band;

FIG. 2 is a plan view of FIG. l;

FIG. 3 is a view in vertical transverse cross-section taken along the line III-III-III-III of FIG. 2; FIG. 4 is a longitudinal cross-section taken along the line IV-IV-IV'-IV' of FIG. 5, and shows the` second embodiment;

FIG. 5 is a plan view of FIG. 4;

FIG. 6 is a view in vertical transverse cross-section taken along the line VI-VI of FIG. 5; and

FIG. '7 is a view in vertical transverse cross-section taken along the line VILVII of FIGS. 2 and 5, and common to both forms of embodiment.

In these figures, the reference numeral 1 designates the needle body, the front portion of which mounts the weftinserting head (which has not been illustrated in the drawings). The body 1 shown in its extreme outer position is fixed on the flexible band 2 which is constituted in the examples which have been illustrated by two strips 2a, 2b. The said band is provided with perforations 3 in order that the band may be permitted to mesh with a toothed wheel 4 to which is imparted a reciprocating movement of rotation, thereby effecting the to-and-fro motion of the needle. The band 2 is guided at its edges 2c and 2d inside slideway guides 5 and 6 which are fixed on the lay by means of screws 7.

The needle body 1 comprises a front base portion 1a and a rear base portion 1c, which have the maximum width which is compatible with the band. guiding slideways (as shown in FIG. 7). The width of the front base portion 1a is less than the width of the band and is nearly as wide as the distance between the slideways. The underface 1b of the front base portion 1a may thus be perfectly xed on the band by means of two lines of tubular rivets 8. This wide seating makes the front portion of the band 2 perfectly straight both in the transverse direction and in the longitudinal direction and permits its correct engagement in side the guides which are set at intervals along the path of travel of the band through the shed.

The rear base portion 1c of the needle is narrower than the front base portion thereof and is so shaped as to leave the top face of the band free at least on one side.

In the embodiment of FIGS. l to 3, the rear base portion 1c of the needle body covers only a portion of the width of the band between the longitudinal axis thereof to a distance from one edge of the band, thus leaving uncovered the marginal portion 2d. A part of the zone of the perforations is covered and fixed at intervals by a row of rivets 8'. Between these fixation points, the rear 3 base portion 1c is-recessed at 11 so as to permit the tips ofthe teeth of the wheel 4 to pass.

That portion of the guide 5 which is located above the edge 2c of the band 2 is eliminated in the zone of the wheel 4'so as to permit the installation of a guide-plate or retaining member 9 which is secured by means of screws 10 and which covers the entire edge 2c of the strip 2b ofthe band 2 up to the immediate vicinity of the wheel 4, and'limits the lifting movement of the band.

In' the embodiment of FIGS. 4 to 6, the rear base portion 1c covers only the zone of perforations 3 ofthe band 2 and Vthus leaves free'the two edges 2c and 2d of the band 2. The sole 1c is ixed at intervals in the spaces between the perforations 3 byfmeans of a row of rivets 8". Between these fixation points, the sole is recessed at 12 so asto permit the teeth of the wheel 4 to be fully seated in thefba'nd 2.

This form of embodiment makes it possible to place two guide-plates or retaining members 9 and 9', one on each'side of the wheel'4, the guide-plate 9' being mounted in a manner similar to the plate 9. The two edges 2c and 2d are thus covered up to the immediate vicinity of the' Wheel 4, thereby limiting the lifting movement of the band v2 on both sides of the wheel.

That face of each plate 9 and 9 which comes into contact with the band'Z canbe chromium-plated or coated with chemicalfnickel or a mixturehaving a base of polytetrafluoroethylene, or of any other product which has a low coefficient of friction. Y

The guiding of the band in the meshing zone, instead of being eected by the additional plates 9, 9', can be carried out by the slideway or slideways themselves, provided` that they are designed in such manner as to have, in the requisite place, the supplemental width which is necessary to permit said slideways to carry out this function.

Furthermore, vit is possible to substitute for the guideplate or guide-plates either one or a number of rollers or a doubleY roller, so as t0 limit the lifting'movement of the band. The alternating movement of rotation which is imparted to such rollers by the displacement of the band can be stopped at each end of travel of the band by means of contact 'keys which are momentarily brought to bear onvthe rollers.

It is clearly understood that theV present invention is not limited to particular forms of embodiment and that it will be possible to devise alternative forms, detail improvements and uses of equivalent means without thereby departing either from the scope or the spirit of the invention.

What I claim is:

1. A weft inserting mechanism for a loom comprising a flexible band having a longitudinal middle zone and two edges, perforations along said longitudinal middle zone, twospaced slideways in which the two edges of the band are respectively slidably mounted for reciprocal sliding movement, a reciprocating driving toothed wheel having teeth engaged in said perforations, a weft inserting needle having a body with a at base applied against one face of said band and having a front portion and a rear portion, the width of said front portion being less than the width of the band and being substantially equal to the distance between said slideways, said rear portion being narrower than the distance between said slideways and exposing at least one longitudinal portion of said band located between the edges and the perforations, and a retaining member mounted upon at least one of said slideways and extending lengthwise in the vicinity of the teeth of said driving wheel and crosswise toward the longitudinal middle zone `of said band close to said perforations.

2. A weft inserting mechanism in accordance-with claim l, wherein said rear portion of said weft inserting needle has a longitudinal middle portion having recesses adapted to clear the teeth of said driving wheel.

3. A weft inserting lmechanism in accordance with claim l, wherein said rear portion of said weft inserting needle bears on said band only between one of said slideways and said longitudinal middle zone.

4. A weft inserting mechanism in accordance with claim l, wherein said-rear portion of said weft inserting needle has a longitudinal middle portion which bears on said band only along said longitudinal middle zone and hals recesses adapted to clear the teeth of said driving w eel.

References Cited in the le of this patent UNITED STATES PATENTS 2,125,894 Dewas Aug. 9, 1938 2,151,085 Dewas Mar. 21, 1939 2,548,662 Fletcher et al.V Apr. 10, 1951 

1. A WEFT INSERTING MECHANISM FOR A LOOM COMPRISING A FLEXIBLE BAND HAVING A LONGITUDINAL MIDDLE ZONE AND TWO EDGES, PERFORATIONS ALONG SAID LONGITUDINAL MIDDLE ZONE, TWO SPACED SLIDEWAYS IN WHICH THE TWO EDGES OF THE BAND ARE RESPECTIVELY SLIDABLY MOUNTED FOR RECIPROCAL SLIDING MOVEMENT, A RECIPROCATING DRIVING TOOTHED WHEEL HAVING TEETH ENGAGED IN SAID PERFORATIONS, A WEFT INSERTING NEEDLE HAVING A BODY WITH A FLAT BASE APPLIED AGAINST ONE FACE OF SAID BAND AND HAVING A FRONT PORTION AND A REAR PORTION, THE WIDTH OF SAID FRONT PORTION BEING LESS THAN THE WIDTH OF THE BAND AND BEING SUBSTANTIALLY EQUAL TO THE DISTANCE BETWEEN SAID SLIDEWAYS, SAID REAR PORTION BEING NARROWER THAN THE DISTANCE BETWEEN SAID SLIDEWAYS AND EXPOSING AT LEAST ONE LONGITUDINAL PORTION OF SAID BAND LOCATED BETWEEN THE EDGES AND THE PERFORATIONS, AND A RETAINING MEMBER MOUNTED UPON AT LEAST ONE OF SAID SLIDEWAYS AND EXTENDING LENGTHWISE IN THE VICINITY OF THE TEETH OF SAID DRIVING WHEEL AND CROSSWISE TOWARD THE LONGITUDINAL MIDDLE ZONE OF SAID BAND CLOSE TO SAID PERFORATIONS. 